Organ action



Aug. 21, 1928. 1,681,547

M. MAAG ORGAN ACTION Filed 17, 1923 2 Sheets-Sheet 1 I N V EN TOR. Wm W029 ATTORNEY- M. MAAG ORGAN ACTION Filed Aug. 17, 1923 2 Sheets-Sheet 2 EjzL INVENTOR.

cfifoaxelfagq W/ A TTORNEY Patented Aug. '21, 19

Mex ane, orscnwnlvrnnninenn swIrznn Ann.

ORGAN Ac'rIoN.

Application and August. 1111923. fsriai. no. 657,910: I i

fl'The p-resent invention relates to a pneumatic, and electro-pneumatic actuating mechanism for musical instruments equipped with pneumatic tone-producers, and its. principal 6 object is, to regulate the tone poweror loudness ofthese tone producers by varying the wind pressure supplied thereto according to they will of theplayer. 7

The present invention may be used with any. tone-producen-the pitch of which remains; constant with varying wind pressure. It is well known that certain reeds and plpes, either of special form or equipped with compensating devices, maintain a const'ant pitch for varying pressures of air to which my invention is applicable. Another principal invention. is to provide a construction permittingrthe operator to vary the tone intensity or loudness of any individual pipe or reed by varying the degree of pressure upon the key bv means ofwhich that pipe or reed is played.

Another object of the; invention is to provide means to supply wind directly to the tone-producers at any desired pressure, over a wide range by varying the pressureupon the keys. v a

Another object of the invention is to dis-; pose the valve in the wind supplying mecha-. nism for the tone-producers so that the pressure within the chest directly associatedwith the tone-producer may be varied, and also,

to. so position the pallet that it will open into this chest directly adjacent the tone-producer. Another object of the invention is to provide a pressure .regulatingdevice operated by depressing the keys so that the pressure admitted to. the tonereducers connected with that key may be directly controlled and the'intensity ofits tone widely varied.

tach pneumatically or electrically controlled means to the tone-producer pallets so that these pallets may be automatically controlled in Fig. 1, portions being broken, away show-.

object of thelpresent QAnot-her object of the invention ,is to at means controlling the wind" plied to the tone -producers. I It; will be} understood, however, that certain featuresfof EicE.ff a

the invention can he otherwse embodied and adapted for other types of instrumentsand that the drawings'arefnotto; beconstrued as defining or, limiting thefscope of thekinventiomthe claims appended tojthisspecifica j 'tion being relied upon for thatv purpose.

In the drawings .1

Figure l is. a cross: sectional viewthrough the keyboard and wind chest of an organy Fig. 1 1s aviewof adetail g Fig.2 is [plan vlew of the inn sectionstaken upon lines A-jAtndB-B Fig. 3. 's aview similar toIFig; 1. showing' a pneumatic relay mechanism for controlling the wind: pressure admitted to the tone pro ducer,- and, ".1 H I e shows electropneuniatic m. I controlling the wind pressure; 2 c y y In theabovementioneddrawings, I 'h'ave shown several embodiments otthe invent-ion Wl'llCl'L are now deemed preferableehut it is to beunderstood thatchanges and modifications maybe made within the scope of the'fappended claims without departing from the spiritiof;the'invention p comprises the following principalf par First, a'keyboardthe keys, of which are resiliently supportedat one endso that they may be depressed different amountsby applying different amounts of pressure'thereto; second, pneumatic or electrical means controlled thereby so that when the key is; depressed these will be actuated'tovary apressure'control mechanism; third, a source of air under pressure;fourtln a wind chest, the pressure in whichis regulated by the position of the pneumatic'or electric means; fifth, a wind ,Briefly; my invention in its'bro'adest aspect chest having a? bellows therein; sixth, a pallet opening into a wind chest directly associated with the tone-producers; and" seventh, pneumatic orelectrical means connecting the last named pallet withsaid bellows to control the pressure of air supplied to said tone-producer.

Referring more in detail to the figures of the drawings. and particularly to Figs. 1, 2 and 3, I provide a wind chest 1 which may Inn be filled with air under pressure by any suitablemea ns' through opening- 2? The pressure of this air within this chest 1 may be indicated by 1). In the upper surface of this chest is formed an opening 3 which may be closed by a pallet 4: opening within the chest 1. The opening 3 extends into a second wind chest 5, the upper surface of which is also provided with an exhaust opening 7 which may be closed by pallet 8. The pallets 4 and 8 are connected together by a suitable wire 11 is not being played,'the pallet 4 rests i O=th e area of outlet opening 7 against its opening 3 by reason ,of the pressure of the air within chestl and of spring 14. The opening 3 is therefore maintained closed and the exhaust opening 7 entirely open. If pressure is placed upon thekey 11, theair pressure supporting pallet 41s overcome and spring 14 is compressed sothat the pallet 4 opensand the pallet 8. entirely closes. With the pallets 4 and 8 in these positions air rushes from the wind chest 1 to the chest 5 where it will develop a pressure equal to p. .If, however, key 11 is not pressed to its lowermost position to entirely close pallet 8, compressed air not only enters chest abut the air within chest 5may pass out through opening 7 to atmosphere undena certain pressure, p,. For thecalculation of the latter it may be considered that the amount of air being exhausted from the chest 5 equalsthe amount of air admitted. t I

Taking the product of theopenings'and the difference of air pressures between the adjacent chests as a measure. for these amounts of air, we may obtain the following equation: I I

+l P0) +211 inwhich A I=the area'of inlet opening 3 b=the pressure of the atmosphere p=thc air pressure in wind chest 1 p =the air pressure within the chest 5;

Itis this lastfactor which we wish to obtain. From theaboye equation wenriy obtain the following:

' (P P1 )P1 I-.p==(O+I)piand In other words. pressure p within chest 5 forming the wind tunnels fort p will'equal p. When O=I, then closed then will equal zero, in which case p p. Therefore by supplying pressure to key 11 to'a greater or less extent, the pressure'within the chest 5 may be varied to any desired pressure from zero u to the pressure p supplied by the pump to t e chest 5; The above descri Jed valve mechanism comprises a pressure regulating valve and, by varying the position of the key, widely varying pressures can be obtained, within the chest 5. By increasing the pressure on key 11, its position is varied toopen the pallet 4 to a greater extent andthus increase the pre'sure within chest 5. Also, as soon asthe pressure u on the key 11 is released to any extent, the ey moves upward, thus serving to move the pallet 4 to its closed position and thus reducing the pressure within the chest 5. A

Also shown in Fig. lis a section through the respective chests of an instrument havin three sets of tone-producers of different character. This wind chat shown diagrammatically comprises a box 15 divided into upper and lower chests by a horizontal partition 16. The lower space or chest contains walls 17 and 18 dividing, it into three inde, endent spaces e three sets of tone-producers. The strips 17 and 18 also extend through the upper portions of the wind chest 15. This upper wind chest, it will be understood, is divided rectangularly l2 means of partitions into as many indepen ent chest or spaces for each register or stop as there are keys in the keyboard, several of these being shown in Fig. 2. Above these upper chests, the tone-producers are placed as will be understood by reference to Figs. 1 and 2. These are of successively higher pitch corresponding to the different keys on the keyboard.

Assuming that the wind tunnels 2328, etc., are filled with compressed air from any suitable source, the tone-producers of. the pitch corresponding to the key 11 will sound while that key is depressed. The tone-producers will not. however. sound when the wind tunnelsare closed and therefore do not contain the compressed air. As the means for supplying pressure to the tunnels 2328,

etc, iiorm no partof theinvention, they have 21; shown directly attached to the chest 20,

shown in Figs'l and 2. This chest is connected with its wind tunnel 23 through an opening 22. The opening 22 is adapted to be closed by a pallet24r so disposed that it may open into the tone-producer chest 20'. This pallet24 is connected through a wire 25 to the movable portion of a. bellows fitted to the lower portion. of the chest or tunnel 23. The space within. the bellows 26 is adapted to be connected with the: chest 5 of the pressure regulating device through a pipe or tube 19. In order to make use of this particular stoprepresented by the tone-producer 21, its tunnel or chest 23 therefore must be provided with. air under pressure from the source of supply, thepressure of which being ;0, as before. This pressure, upon one side, acts upon the,- movable portion of the bellows to compress it, thus giving aclosing efiect to the pallet 24. On theopposite side, however,

- the pressure 3) acts directly upon the pallet 24. to open. it. If the active surfaces of the bellows 26 and the pallet 24 were equal, then the opening and closing action upon the pallet 24 would be equal and it would remain closed in spite of. the chest 23 being under pressure.

As soon, however, as key 11 is depressed, air under a predetermined pressure as described above; is introduced within the bellows 26', this pressure acting upon the lower side of the bellows forcing it toward its open position and. therefore tending to open the pallet 24, through. wire 25. As soon as pallet 24 opens, wind enters the space 20 and thus the tone producer speaks. A certain pressure p is developed. within chest 20 which on one side causes a current of wind through the tone-producer21 and to the opposite side tends: to close pallet 24. This pressure may be. determined somewhat as follows: Pressure 71 from the space 23 tends to open the pallet 24- and also attempts toclose the bellows thus holding the pallet 24 in one position, The

pressure p, acting within the inner side of the bellows tends'to open thebellows andthus open the pallet 24. A third pressure 79, within the chest 20 tends to close the pallet 24 aszwell as cause the tone-producer to speak. Setting out these forces acting upon pallet 24 and giving the opening pressures and the closing pressures signs, we set the following equation for the balance of the latter;

- or. inother words, p p

inthe chest. 5 oi the pressure: regiflating do. vice;v This, as; we have seen above, may be regulated by applying more: on less. pressure a. the key 11. s

The pipe or: tube 19.- frona each. of the keys 11 notonly extends to a single bellows26 but at the same time; extends; to other bellows 27 which: are mounted. within. the: register tunnel 28- 0t afseparate type Off team-producer indicated at 29. If this, register during operation. is. not tobe sounded, itsv register tunnel 2S- may be closed so that no air under." pressure may enter it. The pressure. 12, within pipe 19' entering; bellows 27 opens the: pallet 30, but in spite of this, with. register tunnel 28 closed from its supply of. compressed air, the tone-producer 29.1 will; not sound;

. The above described mechanism raw-inf. be I lating of air pressure to its tone-producer:

Ifpallet 24 were arranged upon the opposite side of the; opening. 22, as in ordinary organ construction, then therewould beno possibil ity of regulating itsopeniingj by the: counteraction ot pressure-.19 Thepallet in that position could. only be. entirely closed or entirely open for the: reason that any pressurev arising within chest 20*would aid in opening the. al-- let 24. As soon as the opening of pallet lad been. accomplished. by the opening of bellows 26, (connected to paillet 24 by a. suitable lever arrangement it would be held. in its open position. On the other hand, pallet. 24 would.

closev instantly when thepressure was exhausted from thebellows 26 aandthe pressure within the. tunnel 23 alone acted upon the pallet. If, however, a tone-producer applied thepitch of which does. not alter with difiierent pressuresv of wind supplied to it so that it may he. played. at any pressure-to. vary its'loudness, thena construction. must be made use of which allows regulating thepressure and therefore the opening of: the. pallet 24to any desired degree; This is only possible when the pressure generated within the toneprodncer chest 20 counteracts the. opening forces of pallet 24 until a balance between the closing and opening iorces for any pressure pm in. bellows 26 is reached-,1

It. will be: seen. from the above that the pressure within the; chestv 20 always equals the pressure within the chest 5 of the pres-- re re ulatin device. This not only makes g s it possible to sound the tone-producer at any desired degree 01' power but also enables one to 'increaseor decrease the tone power or loudness of the tone-producer at any time during operation. When a small pressure is applied to the key 11, then a small pressure only is developed within the chest 20 and a soft tone is given out. To increase its power, it is only necessary to slightly increase the pressure upon its key 11. The air pressure within the chest 5 being increased as above defined acts upon the pallet 24 so that it will open to develop an increased pressure within the chest 20. If, on the other hand, decreased loudness is desired. a decrease of pressure on the key will accomplish it by minimizing the opening of the pallet 24.

It must be understood that it is not pos sible to bring the tone-producing pressure up to the theoretical maximum as indicated in the equation p niax.=p max.=p. This is for the reason that the tone-producing pressure depends upon the relation of the respective inlet and outlet openings of the chest 20 in the same manner as pressure 72 in chest 5 depends upon the relation between the openings 3 and 7. The inlet to chest- 20 however can be made equal to the full size of the opening 22 whereas the outlet of chest 20 cannot be varied as it comprises the opening through the tone-producer. For this reason the ratio between the outlet and inlet of the chest 20 cannot in any event equal zero, and the tone-producing pressure'cannot be brought up exactly to initial pressure even if pressure within chest 5 equals the initial pressure. It however will approach the initial pressure it the inlet to chest 20 is made as large as possible in proportion to its outlet through the tone-producer 21.

As above described, the pallet 24, disregarding its weight, is just in balance when its particular wind tunnel contains pressure and there is no pressure in the pipe 19. This fact suggests the danger that pallet 24 may not be entirely tight, and a certain amount of wind may pass through the tone-producer even if its particular key is not being played. This danger can be avoided by giving the pallet 24 a certain surplus of closing power while its key is not being operated. This can be accomplished bvmaking'the active surface of the. movable bellows 26 larger than the surface of the pallet 24. Supposing this surface of the bellows is twice as large as that of the pallet 24 then the balance will take place when the pressures are asfollows:

+p2 +2p -p =O.

or. simplifying p =2p p. In other words, when 29 p p, or the pallet 24 is pressed against its opening 22 with a. surplus pressure which equals pressure p and therefore this pallet may be maintained pressure tight. If

we make 75 it follows that pallet 24 will 7), that is to say when N for chest 5 equals 1. Increasing 19 increases until p equals p and 1) equals 1).

This difference of arrangement as compared with that first described results in the fact that. the pallet 24 will not open as soon as the key is pressed down but will open only when it has been pressed to such an extent that has reached of the initial pressure p. This might make it awkward for the player to determine exactly what pressure of the key must be given to just make the tone- .ucer speak supposing that the key in its 'mal posit'on rests on spring 14. This dif- :lty can then be overcome by giving the key a certain amount of movement before it lttll'lli? the spring 14 as shown in Fig. 1. Then a v= y light pressure upon the key will press it far within the chest 5 which will equal /2 of the initial pres ure supplied by the pump. At this moment. the key will just come into contact with the spring 14 and the position at which the pallet 24 will be in balance can be easily determined. Giving the key 11 a sl' 'hily increased pressure, pallet 24 will instantly open and its opening can be regulated to any desired degree by supplying and alter ing the pressure upon the key. The only difference therefore consists in the fact that only of the range of pressure p between 0 and can be used for the regulation of loudness of the tone-producers while the remainder of the range serves only in overcoming the surplus of the closing effect of the pallet 24 introduced by the increased size of the bellows 26.

Mechanisms for large instruments are diagrammatically shown in Figs. 3 and 4. Referring first to Fig. 3, it will be seen that the chest in which the variable pressures controlling the intensity of" tone are produced is in connection with a single bellows 31 through pipe 10. The construction shown in Fig. 3 shows the mechanism for producing a given tone in three difl'erent registers or stops while a greater number of stops may be enqiloyed extending to the right of the tniree shown. The single bellows 31 is mounted in a separate tunnel 32 running in the same direction as the tone-producers of any given register. This tunnel 32 may be filled with compressed air from the source of supply. The movable member of the relay bellows 31 is mechanically connected with the pallet 33 by a suitable wire. this tunnel 82 opening into another tunnel 34. All the bellows 35 operated by one key 11" on the lawenough to develop a pressure boardare pneumatically controlled from the pressure developed within the single tunnel 34. The active surface of the pallet 33 is shown as being of the same size asthe movable member of .thebellows 31.

vhich admit air to the individual tone-prolucers as 2'1-29and 41 may be of approximately one half the size as the bellows 35.

vAs :above described, as soon as the pressure within the chest 5 is produced within the bellows 31, the pallet .33 will open admitting pressure to the tunnel 34. This pressure will exactly reach that'in chest 5*when it closes pallet 33. At that pressure, the bellows 35 willbe expanded thus opening the pallets 36. This takes place when the respective chests 37 are not under any initial pressure. These chests 37 however must be under pressure when the tone producers associated therewith areto'be sounded. This, of course, takes place when pressure isadmitted to the chambers .37 in any preferred manner, not shown. This pressure within chests 37 will not permit pallets 36 to open until the pressure with in the bellows 35 exceeds half the pressure within the chest 37. The pallets 36 at that pressure will open, the pressurecontrolling bellows 31 equals the active surface of pallet J 33, then pressure p within tunnel 34. will always equal p within the chest 5. The

, pressure ga within the chests opening to the tone-producers will therefore vary with this pressure p by reason of the action of the bellows 35 according to the equation p3=2p p.

In other words, the pressure of the air admitted to the tone-producer can be regulated in the same manner as before, the only change being that an intermediate or relay valve 33 is introduced. WVith this construction, any desired increase of tone power can be accomplished by merely introducing, an in creased pressure upon'the key which causes pressureito'be built up within the chest 5 and thetone-producers chests.

To decrease the tone power orintensity' necessitates a separate device,which will enablethe tunnel 34 to be exhausted to a greater or less extent. -Releasing pressureupon the key causes tighter closingof the pallet 33 so that unless exhausting means are provided,

the pressure once established in tunnel 34 would be retained within this tunnel and bel-f lows'35 would remain expanded as j long as I this pressure was maintained. To overcome Pallets as.

this difliculty, the tunnel34 is connected to and, as soon as the pressure in pipe l9 drops slightly, its pressure is less than that within tunnel 34. The port 38 is thereforeopened slightly until the air is exhausted from tun.- nel34 and until the pressure within bellows 39 again equals it and closes the opening 38.

The pressure to the tone-producers theret'ore is regulated both up and down in accordance with the pressure in chest 5.

By referring to Fig. 4 it will be seen that a third method of obtaining varying loudness of the tone-producers by varying the pressure upon the keys has been provided. This method is operated by electro-magnetic means. Below each of the keys 11 is located a coil 50 forming the primary windings of a transformer to which alternating current may be supplied from any suitable source. Within this primary coil 50 is a secondary winding 51. On the key 11 is mounted a piece of soft iron 52, the position of which. relative to the coils 50 and 51 varies with the different positions of the key. The effect of this iron 52 during playingis to vary the current flowing through the secondary winding 51. This is for the reason that the magnetic flux is varied with different positions of the iron 52. Wires 53 extending from the secondary winding 51 lead to the winding of a solenoid 54. From theiabove it will be seen that variable current will be induced in: this winding 54 due to the position of the key 11",. is depressed the further the iron. piece 52 will enter the space within winding 51 and thus increase the current induced within this secondary winding. i

Within the solenoid winding 54 is an armature 55 urged downward by a-suitably mounted coiled spring 56. The effect therefore of varying currents within winding 54 is to vary the positionof the armature 55. Increased current within the solenoid 54 will tend to force the armature 55 upward against the pressure of. the spring 56. 7

Attached to the armature 55 by means of suitable wires are. pallets 57 and '58 which control openings formed in a chest 32 replacing chests 1 and 32shown in Fig. 3. This chest 32 may be supplied with air under pres-- sure from any suitable source. The effect of varying the movement of the armature 55 and the pallets 57 and 58 is to vary the inlet and outlet openingsiof air tunnel 60. With the pallets 57 and 58 inrthe position shown in Fig.

4, air tunnel 50 which takes the place of chests The further key 11? 5 and 5 shown in the above described figures is without air pressure. As soon as any pressure is placed on key 11 and armature 55 is raised by the current in solenoid 54 pallets 57 and 58 open to an intermediate position.

With the pallets in this intermediate position a pressure will be built up in tunnel 60. This pressure will expand the bellows 31 and open the pallet 33 in the same manner as in the form of the invention previously described. This pressure within bellows 31 will be the same as that in tunnel (30 which pressure will be admitted to tunnel 34 and to the toneproducer chests 20 in the manner which will be understood from the description of the other forms of the invention.

Tunnel 60 extends to the inside of a bellows 39* the movable side of which presses against an openin 38 in tunnel 34". It then the current in solenoid 54. is weakened and the pallets 57 and 58 moved downward to reduce the pressure within tunnel 60 the pressure in tunnel 34 will be exhausted past bellows 39 until the pressure in tunnel 34;" equals that in the tunnel 60. Varying the positions therefore of the pallets 57 and 58 will permit varying the pressures within the tunnel 3i either to increase or decrease the pressure supplied to the tone-producers 21". 29", ll, and so forth.

What I claim is:

1. A pneumatic action for organs comprising in combination, a plurality of keys, a plurality of tone-producers, means to supply air under pressure to said tone-producers, pallets in said air supplying means, a pallet actuated by said key to vary the pressure within individual wind chests, bellows, conduits connecting said wind chests with their bellows, means connecting said bellows to their respective pallets whereby varying the positions of said keys individually varies the positions of the bellows and said pallets and the pressure of air supplied to said tone-producers varies directly with the positions of said keys.

2. A pneumatic action for organs comprising in combination, a plurality of keys, a plurality of tone-producers, means to supply air under pressure to said tone-producers,

allets in said air supplying means, actuated by said keys to vary the pressure within individual wind chests, bellows of larger area than said pallets, conduits connecting said wind chests with their bellows, means conmeeting said bellows to said pallets whereby varying the positions of said keys varies the positions of the bellows and said pallets and the pressure of air supplied to said toneproducers varies directly with the positions of said keys.

' 3. A pneumatic action for organs comprising in combination, a tone-producer, a wind chest therefor and directly associated therewith, a pallet positioned and opening therein, means to supply air under pressure to said wind chest through said (pallet, and means tovary the position of sai pallet to vary the tone intensity of said tone-producer. Y

4. A pneumatic action for or ans compris-' 5. A pneumatic action for or us comprising in combination, a tone-pro ucer, a wind chest therefor, a key for operating said toneproducer, a pallet positioned within and opening within said wind chest, means to supply air under pressure to said wind chest through said pallet, and neumatic means connected to said pallet an actuated by said.

key to vary the position of said pallet and the pressure supplied to said tone-producer.

6. A pneumatic action for organs comprising in combination, a tone-producer, a wind chest therefor, a key for operating said toneproducer, a pallet positioned within and opening within said wind chest to admit air under pressure thereto, pneumatic means connected to said pallet, and pallets actuated by said key to supply air under variable pressures to said pneumatic means whereby the pressure supp ied to said tone-producer may be varied. I

7 A pneumatic action for or nscomprising in combination, a tone-pro ucer, a wind chest therefor, a key for operating said toneproducer, a pallet positioned within and opening within said wind chest to supply air under pressure thereto, a bellows positioned within a portion of the air supplying means, means connecting said pallet and bellows whereb pressure on said bellows holds the pallet in its closed position, and means to supply air under variable pressures to within said bellows to open said pallet and admit air under variable pressures to said toneproducer.

8. A pneumatic action for or us comprising in combination, a tone-pr ucer, a wind chest therefor, a key for o crating said toneproducer, a pallet positioned within and opening within said wind chest to sup 1y air under pressure thereto, a bellows positioned within a portion of the air supplying means, means connecting said allet and bellows whereby pressure on sai bellowsholds the pallet in its closed osition, means to su ply air under varia le pressures to within said bellows to open saidpallet and admit air under variable pressures to said tone-producer, and means permitting air within said bellows to be exhausted when pressure on said key is reduced.

9. A pneumatic action for organs comprise ing in combination, a tone-producer, a wind said bellows to open said pallet and admit air a under variable pressures to said tone-pro- --ducer, andan auxiliary bellows connected with said first mentioned bellows and adapted to permit air in said first bellows to be exhausted when pressure on said key is reduced. i

10. A pneumatic action for organs comprising in combination, a tone-producer, a Wind chest therefor, a key for operating said tone-producer, a pallet positioned within and opening within said wind chest to supply air under pressure thereto, a bellows positioned within a portion of the air supplying means, means connecting said pallet and bellows whereby pressure on said bellows holds the pallet in its closed position, and means actuated by thekey to supply air under variable pressures to within said bellows to open said pallet and admit air under variable pressures to said tone producers.

11. A pneumatic action for organs comprising in combination, a plurality of toneproducers, individual wind chests therefor, pallets positioned and opening therein, means to supply air under pressure to said wind chests through said pallets, and, unitary means to vary the positions of said pallets to vary the tone intensity of said tone-producers. g

12. A pneumatic action for organs comprising in combination, a plurality of toneproducers, individual wind chests therefor,

pallets positioned and opening therein, means to supply air under pressure to said wind chests through said pallets, and unitary pneumatic means to vary the positions of said pallets to vary the tone intensity of said toneproducers.

13. A pneumatic action for organs com,

prising in combination, a plurality of toneproducers, individual wind chests therefor, a key for actuating said tone-producers, pallets positioned and opening therein, means to supply air under pressure to said wind chests through said pallets, and unitary means actuated by said key to vary the positions of said pallets to vary the tone intensity of said tone-producers.

14:. A pneumatic action for organs comprising in combination, a plurality of toneproducers, individual wind chests therefor, a key for operating said tone-producers, pallets positioned within and opening within said Wind chests, means to supply air under pressure to said wind chests through said pallets,

and unitary pneumatic means connected to said pallets and actuated by said key to vary the position of said pallets and the pressure supplied to said tone-producers;

15. A pneumatic action for organs comprising'in combination, a plurality of toneproducers, keys for operating saidton'e-producers, individual Wind chests therefor, pallets opening therein, means to supply air under pressure to said wind chests through said pallets, pneumatic means to vary the positions of said pallets to vary the tone intensity of said tone-producers, and electro-magnetic means to vary the pressure within the pneumatic means in accordance with the position of the keys. c

16. A pneumatic action for organs com prising in combination, a plurality of toneproducers, keys for operating said tone-producers, individual wind chests therefor, pallets opening therein, means to supply air under pressure to said wind chest through said pallets, pneumatic means to vary the positionsof said pallets to vary the tone intensity of said tone-producers, transformers associated with said keys, and electro-magnetic means actuated thereby to vary the pressure within the pneumatic means in accordance" with the position of the keys.

In testimony whereof, I hereto affix my signature.

MAX MAAG. 

